The present invention relates to a health food/dietary supplement containing as its characterising components an alkanoyl L-carnitine selected from the group comprising isovaleryl L-carnitine and propionyl L-carnitine or their pharmacologically acceptable salts or mixtures thereof and an extract of Silybum marianum (milk thistle) or its active components, among which most notably silymarin.
It has been found that the above-mentioned composition is extremely effective in exerting a potent protective action on liver function and integrity against lesions induced by various exogenous and endogenous hepatotoxic agents owing to the unexpected synergistic effect exerted by the interaction of its components.
Isovaleryl L-carnitine, a natural component of the carnitine pool, presents a specific activity at lysosomal level and on the cytosolic movements of calcium. It is therefore capable of intervening in proteolytic processes such as occur during intense and prolonged effort, and of protecting a number of organs such as the liver against the action of toxic substances.
Propionyl L-carnitine exerts an intense antioxidant effect and is particularly effective in improving the peripheral circulation and cardiac function.
In addition, muscular carnitine transferase possesses higher affinity for propionyl L-carnitine than for L-carnitine, and consequently propionyl L-carnitine possesses a higher degree of specificity for cardiac and skeletal muscle. Moreover, propionyl L-carnitine transferase by transporting the propionyl group increases the uptake of this component by the muscle cells, which may be particularly important for energy purposes, in that the propionate can be used by the mitochondria as an anapleurotic substrate and supply energy in the absence of oxygen.
The milk thistle is an indigenous plant cultivated for centuries in the Mediterranean region and South Western Europe and naturalised in most of Europe. It is also naturalised in North America, particularly California; in South America it is present from Uruguay to Chile and Ecuador; in Australia it runs wild; it is commonly found in abandoned fields, old pasture land and at the roadside.
The efficacy of the seeds of Silybum marianum or the milk thistle in preventing or treating various forms of liver or biliary dysfunction has been known for over two thousand years and is deeply rooted in popular tradition.
In 1968, silymarin, a flavanolignan complex was isolated from the plant. This consists mainly of three flavanolignans, silybin (silybinin), silychristin and silydianin. Other flavanolignans present are: dehydrosilybin, 3-deoxysilychristin, deoxysilydianin (silymonin), silyandrin, silybinome, silyermin and neosilyermin. Other constituents are apigeninin and silybonol; a fixed oil (16-18%), composed mainly of oleic acid and linoleic acid, in addition to myristic, palmitic and stearic acids.
In recent decades, few principles of vegetable origin have been studied as thoroughly as silymarin.
Its main activity is liver-protective and antioxidant. The liver-protective activity of silymarin has been demonstrated in numerous experimental models in which liver damage is induced by toxic substances, including carbon tetrachloride, galactosamine, thioacetamide, hepatotoxic cold-blooded frog virus, lanthanides and the toxins of Amanita phalloides, phalloidin and xcex1-amanitin.
The liver-protective efficacy is based on various distinct mechanisms of action. Silymarin stimulates RNA polymerase A, increasing ribosomal protein synthesis and causing activation of the regenerative capacity of the liver through cell development. Silymarin interacts with the membranes of liver cells, blocking the binding sites and preventing intake of toxins, as demonstrated in rabbit liver microsomes and in mononuclear lipid layers. It is strongly antioxidative (free radical scavenger activity 10 times greater than that of Vitamin E), in that it blocks the release of malonyldialdehyde and antiperoxidative activity.
Clinical trials have suggested that preliminary treatments with silymarin inhibit the liver damage induced by alcohol, industrial chemicals and psychotrope drugs, accelerating the normalisation of impaired liver functions.
The patients receiving silymarin show a rapid improvement in elevated serum levels of glutamic-oxalacetic transaminase (GOT), glutamic-pyruvic transaminase (GPT) and xcex3-glutamyl transpeptidase (xcex3-GT).
The therapeutic activity of silymarin as a drug is extensively documented against liver damage, in chronic inflammation support treatment and in cirrhosis, including chronic hepatitis and fatty infiltration of the liver caused by alcohol and other chemicals. For the purposes of infusions, silbinin preparations are used for support treatment in cases of poisoning due to the toadstool Amanita.
In the herbalist or food product sector, the seeds of the plant or an extract of the seeds are used in tea, capsules, tablets and herb teas, mainly as a liver detoxifier.
The commercial preparations of milk thistle include ethanol extracts of seeds and/or fruits, pills or capsules (35-70 mg) standardised to 70% silymarin, in average daily doses of 200-400 mg.
It has now surprisingly been found that a composition containing as its characterising components a combination of:
(a) an alkanoyl L-carnitine selected from the group consisting of isovaleryl L-carnitine, propionyl L-carnitine or their pharmacologically acceptable salts or mixtures of the same; and
(b) an extract of Silybum marianum standardised to at least 70% silymarin by weight,
constitutes an effective health food/dietary supplement exerting a potent protective action on liver function and integrity against lesions induced by various exogenous and endogenous hepatotoxic agents owing to the potent and unexpected synergistic effect exerted by its components.